Rotary toothbrush



Nov. 10,1925. 1,561,062

S. W. DOUGLAS ROTARY TOOTHBRUS H File March 13, 1323 2 Sheets-Sheet 1 Quinn 01:

SMDO ay/cz 5 I atfozneq Nov. 10, 1925- S. W. DOUGLAS ROTARY TOOTHBRUS H Filed March 13, 1923 2 Sheets-Sheet 2 Patented Nov. 10, 1925.

UNITED STATES SMITH W. DOUGLAS, 011 E'UDORA, ARKANSAS.

ROTARY roormmusn.

Application filed March 13, 1928. Serial No. 624,754.

To all whom it may concern:

Be it known that I, SMITH W. DOUGLAS, a citizen of the United States, residin at Eudora, in the'county of Chicot and tate of Arkansas, have invented certain new and useful Improvements in Rotary Toothbrushes and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to a rotary toothbrush.

It is aimed to provide a novel durable structure which enables the bristles to better cleanse and polish the exposed surfaces of and between the teeth by an up and down as well as rotary motion.

Another object is to provide a construction having a novel adjustable protecting 2 means for the mucuous membrane of the mouth.

A third object is to provide a novel form of gearing or drive means and mounting casing therefor.

Various additional objects and advantages will become apparent: from a consideration of the descript1on following, taken in connection with accompanying drawings illustrating an operative embodiment.

In said drawings v s Figure 1 is a view of the improved toothbrush in side elevation;

Figure 2 is an edge elevation thereof;

Figure 3 is a central longitudinal sectional view taken on the line 33 of Figure 2;

Figure 4 is a central longitudinal sectional view taken on the line 4-4 of Fig- "ure 1;

Figure 5 is a transverse sectional view taken on the line 5-5 of Figure 1;

Figure 6 is a detail perspective view of the protector alone;

Figure 7 is a longitudinal sectional view through a modified form, and

Figure 8 is a longitudinal sectional view taken at a right angle to Figure 7 and through the same modified form.

Like reference characters designate like or similar parts in the different views.

Referring specifically to the device of Figures 1 to 7, abrush head 10 is provided wh1ch may have an attaching sleeve 11 and bristles or the equivalent at 12. The attaching end of sleeve 11 may be square. "Said end fits a corresponding end portion 13 of a rotary drive shaft 14 friction tight so as to be removable.

A suitable closed protective casing is provided at 15, preferably being generally cylindrical and being in sections 16 and 17 separable from each other along the line 18. The sections 16 and 17 may be held together in any suit-able manner and for instance by means of bolts at 19 passing therethrough. At the forward end, sections 16 and 17 have extensions 20 which collectively are cylindrical in order to form a bearing in which shaft 14 is journaled. Longitudinal displacement of the shaft 14 is prevented in any suitable way as for instance by a collar 21 and a bevel gear wheel 22 both carried by said shaft and arranged on opposite sides of and engaging the bearing Gear wheel 22 meshes with a larger bevel gear wheel 23 located within the casing 15 and keyed to a shaft 24. Shaft 24 is rotatable and also has a pinionor spur gear wheel 25 keyed thereon which mwhes with a larger pinion or spur gear wheel 26 keyed to a rotatable shaft 27. A smaller pinion or gear wheel 28 is also keyed to shaft 27 and is adapted to be operated or turned, in order-to turn the brush head 10 throu h the medium of the gearing described, by manual depression of a plunger 29. This plunger has a bar 30 slidably mounted through an opening 31 in the section 17. The bar 30 has a rack or spur teeth at 33 which mesh with the teeth of pinion 28. A button or thumb piece to facilitate manipulation of the plunger is Drovidarl at 34. De.- pression of the bar 30 is accommodated by a dependent receptacle 35 on section 16. This dependent also forms anabutment for the fin .er to facilitate grasping and effective ho ding of the casing.

Bar 30 is provided with a lateral lug at 36 through which one end of a power spring 37 is fastened as by rivets 38. The other end of said sprin 37 is fastened as by rivets -39 to the sectlon- 16. Spring 37 is generally ofU-shape andof leaf form tensioned to se arate at its attached ends so as to urge t e plunger 29 to projected position-which movement is limited by the lug 36. Depression of plunger 39 will rotate the gearing so as to rotate the brush head 10 in one direction. Af r depressing F be shifted at will in order to movement, the plunger is released and is restored to uppermost position by spring 37 with the gearing turning the brush head 10 in the opposite direction.

The shafts 24 and 27 are journaled in semicyl'indrical bearing extensions or flanges 40 and 41 integral with the sections. 16 and 17.

The shaft 14 is housed by a tube 42 journaled on the bearing 20 but with sufiicient frictional engagement to remain in position to which it may be adjusted. Displacement of the tube 42 is preventedas by a screw or lug 43 carried thereby and extending into an annular groove 44 provided exteriorly on bearing 20. A manipulating arm or thumb piece 45 extends from the sleeve 42. The forward end of tube 42 terminates in a spoon or other shaped protector 46 extending over the brush. Through manipulation of the arm 45, the position of spoon 46 may be varied relatively to the brush head accordin to the position in which the device is he d and in which the brush is working in the mouth. Theprotector 46 prevents-en- I gagement of the brush bristles 12 with the mucous membrane of the mouth and eflectively prevents brush head 10 from dis engaging. shaft 14 ina direction toward the] distal end of the brushhead. The lumen or passageway of protecting tube 42. is ofsuflicient caliber to permit it to be slipped off over brush head IOa-fter loosening said screw 43.

In o ration, plunger 29 is normally in its pro ected position where outward movement is limited by engagement of lug 36 with the casing'section 17. The casing is 40 held in the hand and the thumbor a finger depresses the button 34 so thatthe bar 30 is depressed causing teeth 33 to rotate gear whee 28 and accordingly its shaft 27. Shaft 27 rotates gear wheel 26 which in turn rotates gear wheel 25, shaft24, gear wheel 23,

gear wheel 22 and shaft 14. Shaft 14 rob tates the brush head 10 which is disposed in brushing engagement with the teeth. By means of a thumb or'a finger, arm 45 may so dispose the protector 46 relative to the bristles 12 that they will not engage the mucous menr-' brane of the month. After depression of,

the button 34, the same, is released by the thumb or finger whereupon the spring 37 which has been tensioned through the depression of the plunger, will expand at its open end thus moving the plunger 29 outwardly and rotating the gearing described in the. opposite direction. The thumb piece 34 is successively depressed and released which therefore imparts reverse rotary .motion to the brush head so that the same will cleanse the teeth through an up and down'moti n and'by the same. mo ion polish This permits removal of the brush head and facilitates cleaning.

the spirit and scope of the invention. For

instance as suggested in Figures 7 and 8, the casing, similar to that at 15 and here designated 50, has an electric motor 51 located therein and adapted to be driven from any suitable source of current under control of an appropriately located switch either on the casing or elsewhere. The main shaft of motor 51 is designated 52 and has a bevel gear wheel 53 keyed thereto which meshes with a bevel gear wheel 54 keyed to a shaft 55 on which a spur gear wheel 56 is also keyed. Gear wheel 56 meshes with a spur gearwheel 57 fastened on a shaft 58 also having a bevel gear wheel 59 fastened thereon. Bevel gear wheel 59 meshes with a bevel gear .wheel 60 which may be carried by a shaft 61 which is similar to the shaft 14, mounted in the same way and adapted to drive the brush head 10 in a similar manner.

-With said motor '51 'in operation, through the chain of gearing mentioned, the shaft 61 that the gearing in this form is of the speed reducing type since the motor will rotate faster than the brush head should rotate and whichis theopposite to the case of the first mentioned form of Figures '1 to 7. Motor 5 1 may be of. any suitable type and if desired may be reversible so that the brush head associated therewith may be ro- I tated in opposite directions alternately as in the case of the form of Figures 1 to 6.

I claim as my invention 1. A motive apparatus having a casing in sections separable on a plane extending substantially longitudinally thereof,.an operating shaft journaled in said casing, split earings comprising flanges carried by both sections, transverse shafts journaled in said flanges, intermeshin gear, wheels on said shafts and on the. rstmentioned shaft, a depressible operating member engaging one of said-gear wheels, and a spring within the casing toreturn the operating member to normal position having one end fastened to one of the sections and the other end fastened to said operating member.

2. A motive apparatus having a casing in sections separable on a plane extending substantially longitudinally thereof, each section having a bearing extension, a rotatable operating shaft journaled in said bearings, bearing flanges on both sections, transverse shafts journaled in said'flanges, intermeshing gear wheels on said transverse shafts and first mentioned shaft, means to drive said gear wheels, consisting of a plunger geared to one of the gear wheels, one of the sections having an opening through which the plunger olperates, the other section having a depen ent receptacle to receive the plunger, and said receptacle also serving as ,a single abutment, a substantially U- shaped spring within the casing fastened at one end to the section, a lug extending from the plunger adapted to abut the interior of the casing to limit outward movement of the plunger, and the other end of said spring being fastened to said lug.

3. A motive apparatus having a casing in sections se arable on a plane extendin substantially ongitudinally thereof, eac section having a bearing extension, a rotatable operating shaft journaled in said bearings, bearing flanges on each section, transverse shafts journaled in said flanges, intermeshing gear wheels on said transverse shafts and .first mentioned shaft, means to drive said ecglear wheels, consisting of a plunger gear to one of the gear wheels, one of the sections having an opening through which the plunger operates, the other section having a dependent receptacle to receive the plunger, and said receptacle also serving as a single abutment, a substantially U-shaped spring within the casing fastened at one end to the section, a lug extending from the plunger adapted to abut the interior of the casing to limit outward movement of the lunger, and the other end of said spring ing fastened to said lug.

In testimony whereof I afiix my signature.

SMITH W. DOUGLAS. 

